大话设计模式-状态模式（大鸟和小菜Java版）

Posted 2021-06-29 香风智乃哈~

正在学习大话设计模式，把书上的代码转换成Java来进行实现，
工作状态-状态模式版的Java代码

状态模式：当一个对象的内在状态改变时允许改变其行为，这个对象看起来像是改变了其类

package 设计模式.状态模式;

//先定义一个接口，当然也可以是一个抽象类，作用是一样的
public interface State {
    public void writeProgram(Work work);
}

package 设计模式.状态模式;

//我把一天所有的状态类都写在一块了
public class ForenoonState implements State{
    @Override
    public void writeProgram(Work work) {
        if(work.getHour() < 12){
            System.out.println("当前时间："+work.getHour()+"点 上午工作，精神百倍");
        }else{
            work.setCurrent(new NoonState());
            work.writeProgram();
        }
    }
}


class NoonState implements State{

    @Override
    public void writeProgram(Work work) {
        if(work.getHour() < 13){
            System.out.println("当前时间："+work.getHour()+"点 饿了，午饭，犯困，午休");

        }else{
            work.setCurrent(new AfternoonState());
            work.writeProgram();
        }
    }
}

class AfternoonState implements State{

    @Override
    public void writeProgram(Work work) {
        if(work.getHour() < 17){
            System.out.println("当前时间："+work.getHour()+"点 下午状态还不错，继续摸鱼");
        }else{
            work.setCurrent(new EveningState());
            work.writeProgram();
        }
    }
}

class EveningState implements State{

    @Override
    public void writeProgram(Work work) {
        if(work.isFinish()){
            work.setCurrent(new RestState());
            work.writeProgram();
        }else{
            if(work.getHour() < 21){
                System.out.println("当前时间："+work.getHour()+"点 加班啊，看会儿动漫先");

            }else{
                work.setCurrent(new SleepingState());
                work.writeProgram();
            }
        }
    }
}

class SleepingState implements State{

    @Override
    public void writeProgram(Work work) {
        System.out.println("当前时间：" + work.getHour() + "点 扛不住了，不行，再熬会儿再睡");

    }
}

class RestState implements State{

    @Override
    public void writeProgram(Work work) {
        System.out.println("当前时间：" + work.getHour() + "点 下班回家了");

    }
}

package 设计模式.状态模式;

//这个是工作类，此时没有过长的分支判断语句
public class Work {
    private int hour;
    private boolean finish = false;
    private State current;

    public Work() {
        current = new ForenoonState();
    }

    public void writeProgram(){
        current.writeProgram(this);
    }

    public int getHour() {
        return hour;
    }

    public void setHour(int hour) {
        this.hour = hour;
    }

    public boolean isFinish() {
        return finish;
    }

    public void setFinish(boolean finish) {
        this.finish = finish;
    }

    public State getCurrent() {
        return current;
    }

    public void setCurrent(State current) {
        this.current = current;
    }
}

package 设计模式.状态模式;

//测试主类，主要测试不同时间点，测试对象的状态
public class Test {
    public static void main(String[] args) {
        Work work = new Work();

        work.setHour(9);
        work.writeProgram();
        work.setHour(10);
        work.writeProgram();
        work.setHour(12);
        work.writeProgram();
        work.setHour(13);
        work.writeProgram();
        work.setHour(14);
        work.writeProgram();
        work.setHour(17);

        work.setFinish(false);
        work.writeProgram();
        work.setHour(19);
        work.writeProgram();
        work.setHour(22);
        work.writeProgram();
    }
}

输出效果：

以上就是状态模式的Java代码实现

参考的大佬文章：https://blog.csdn.net/MONKEY_D_MENG/article/details/5707706